400 Memorandum for U.K.War Cabinet by U.K. Chiefs of Staff Committee

COS(41)230 Final (extract) LONDON, 11 April 1941




We have examined the Memorandum prepared by the Prime Minister of the Commonwealth of Australia [1] and submit our comments below.



2. Mr. Menzies has reviewed (paragraphs 1-5 of his Memorandum) the conclusions of the Singapore Conference Report, 1940, the Chiefs of Staff comments thereon, and the methods by which the existing deficiencies are being made up. He makes particular reference to the views of the Australian Delegation to the Conference that 'in the absence of a main fleet in the Far East, the forces and equipment at present available in this area for the defence of Malaya are totally inadequate to meet a major attack by Japan.' He has therefore asked for statements of the forces, both land and air, and the equipment considered necessary for the defence of Malaya, together with the forces and equipment at present provided and the dates by which the balance will be met.


3. We attach the following statements as Annexes to this paper:-

(a) Annex I: A statement showing the land forces considered necessary for the defence of Malaya, including the total strength in personnel, the forces at present provided and the remainder to be provided, together with the dates by which they will be in Malaya (so far as can be forecast).

(b) Annex II: The total quantity of equipment in main classes to be provided for the forces referred to above, the equipment at present provided, and the remainder to be provided, together with the dates by which it will be in Malaya (so far as can be forecast).

(c) Annex III: The distribution of the strength of the 336 aircraft required 'to give a very fair degree of security' to Malaya indicating the types of squadrons and aircraft, the immediate equipment and the reserves. In addition, the Annex states the present strength of aircraft under the same headings, and states the position regarding re-equipment and reinforcement.

4. An examination of Annex I will show that the land forces in Malaya, with the exception of certain artillery units, should reach their full strength by the end of April 1941.

5. We would point out that it is not practicable to give firm dates regarding the arrival of the various items of army equipment at present deficient in Malaya. Important items of equipment are allocated monthly in accordance with the strategical situation, and the requirements of Malaya are taken fully into account in common with other theatres. It will be seen that, with the exception of anti-aircraft and anti-tank guns, S[mall] A[rms] A[mmunition] and artillery ammunition, the deficiencies in army equipment are not serious.

6. With regard to air force strengths, Mr. Menzies has quoted our opinion that 336 aircraft will give us a very fair degree of security, even if it embraced part of the reconnaissance forces for the Indian Ocean. It is unlikely that this programme will be completed by the end of the year, though that is our present plan.

Nevertheless, in spite of the requirements of the present situation, particularly in the Middle East, we are making steady progress with the re-equipment and reinforcement of the Far East.

7. Even the present situation is by no means critical. For the close defence of Malaya and Burma alone we have at present 118 aircraft, not including the two fighter squadrons (32 aircraft) now forming. The Netherlands East Indies now possess 162 aircraft (with reasonable reserves), of types at least equal in performance to those of the Japanese. Thus the Dutch and ourselves already possess for defence a total of 280 aircraft, and this figure does not include any of the 170 fighters which are now arriving in Malaya from the United States of America, and takes no account of Dutch orders for 245 aircraft from the United States of America, deliveries of which were due to begin last month.

8. The majority of the 450 shore-based aircraft which the Japanese can marshal against us are of obsolete types, and, as we have said, we have no reason to believe that Japanese standards are even comparable with those of the Italians. We have already drawn attention to our experiences, when heavily outnumbered during the Libyan campaign as well as at Malta and in the air defence of Great Britain. We fully realise that our air strength in the Far East is below that necessary for reasonable security in the absence of a Fleet, but we do not consider that in the present situation we are running more serious risks there than elsewhere, though we are making every effort to restore the balance at the earliest possible moment.


9. Mr. Menzies has also asked whether it would be possible for Hurricanes to be made available for Malaya, owing to the reputation this type has achieved.


10. Apart from the necessity for standardisation of types to simplify maintenance and the supply of spares, the use of Hurricanes in the Far East is undesirable, as they could only be provided at the expense of the Middle East, where we are already extended in our efforts merely to replace wastage. The bottlenecks are not availability of aircraft, but packing, tropicalising and shipping capacity. It is therefore of the greatest importance for us to obtain all the aircraft we can for the Far East from the United States. The Buffalo appears to be eminently satisfactory and would probably prove more than a match for any Japanese aircraft.



11. Mr. Menzies has drawn attention in paragraph 7 of his Memorandum to the Prime Minister's telegram of the 23rd December 1940 [2], in which he stated that: 'if Australia is seriously threatened by invasion, we should not hesitate to compromise or sacrifice our Mediterranean position for the sake of our kith and kin.' Mr. Menzies considers it necessary to resolve a general declaration of this nature into a plan of the specific measures that really would be possible in the event of such a contingency arising. There are large forces in the Middle East, including three Australian divisions, and they could not be left to their fate. To withdraw them, however, would take time; shipping would have to be provided, convoys organised and naval protection afforded in the meantime. Much could happen in the Far East during this period.

He further considers that there is need for a definite plan of naval reinforcement east of Suez to the extent to which it might be possible, on a progressive basis, according to events in the Mediterranean.

In our examination below, we assume throughout that the United States is neutral and that a Japanese threat has developed against Australia.


12. Since December, considerable changes have taken place in the military situation. The principal changes are as follows:-

(a) Unfavourable Factors:

(i) The increased importance of retaining adequate naval forces in the Eastern Mediterranean to secure our lines of communication with Greece, to support our land forces in the new operations now opening up in Libya and to supply Malta.

(ii) German heavy ships have been operating against our trade, which has necessitated dispersion of our capital ships for its protection.

(iii) German attack on trade by submarines and aircraft has greatly increased.

(iv) The attitude of France has provided Germany with a means of evading our blockade, and the interception of French convoys is an additional commitment for our naval forces.

(v) In the Far East our strategic position may have been adversely affected by the successful Japanese mediation in the dispute between Indo-China and Thailand, which may give the Japanese an opportunity to establish their forces in Thailand.

(b) Favourable Factors:

(i) The United States have adopted a policy in which, short of being at war, they are virtually allied to the British Commonwealth.

(ii) The situation in Italian East Africa has materially improved, and Italian naval forces in the Red Sea virtually eliminated.

(iii) The Battle of Matapan has reduced Italian naval strength and morale.

(iv) Our defence position in the Far East has been improved both by the strengthening of the garrison and defences of Malaya and Burma and by the Anglo-Dutch-Australian Conversations.

EFFECT OF ABOVE CHANGES ON THREAT TO AUSTRALIA 13. In our view, the general effect of these changes has been to improve the prospective Far Eastern situation. By far the most important factor is the attitude of the United States. Though nominally neutral, they are now so closely identified with our cause that the potential threat of the United States Fleet at Hawaii must alone impose a most powerful restraining influence on Japanese freedom of action to move southwards. It would, we feel, certainly prevent the use of the whole Japanese fleet in support of an expedition to the South Seas.

14. In any event, a threat to Australia, other than raids and attacks on trade, could not arise quickly, since it would first be necessary for the Japanese to seize an advanced base. Before undertaking large-scale operations against Australia the Japanese will also almost certainly consider it necessary to deny Singapore to us as a base and so remove a potential threat on the flank of their lines of communication. In the event, however, of Japanese naval action eventually constituting a real threat to Australia, we have considered below the possibility of making a capital ship force available for the Far East, on the assumption that the United States remains neutral. The question of reinforcement of the Far East in the event of United States intervention has already been dealt with. [3]

POSSIBILITY OF WITHDRAWAL FROM THE MEDITERRANEAN 15. We have considered the question of progressive withdrawal of our forces from the Mediterranean and Middle East theatres. The security of our position in the Middle East remains essential to our strategy for the defeat of Germany. Loss of that position would give our enemies such overriding advantages, strategic, economic and diplomatic, that the course of the war would be considerably prolonged.

16. Any withdrawal, however small, would involve the movement of forces by sea, and the necessity for retaining a strong fleet in the Mediterranean would be increased rather than lessened during the period of such withdrawal. Even if it were decided to abandon our Mediterranean interests, the fleet would have to remain until the end in order to cover the withdrawal of the armies.

HOME WATERS, GIBRALTAR AND CONVOY ESCORT 17. In Home Waters, we must always maintain sufficient force to cover the vital approaches to the United Kingdom. With enemy heavy ships in the Atlantic, we have to draw on our heavy ships in the Home Fleet to assist in escort duty the R Class battleships already so employed. We have always to guard against being forced into a dispersion of our heavy ships and then finding a German heavy ship concentration effected in our Home Waters. There is thus an irreducible minimum for our heavy ship forces in Home and Atlantic waters.

18. At Gibraltar we have maintained a small capital ship and carrier force to prevent the Italian fleet entering the Atlantic, to carry out offensive operations in the Western Mediterranean, and to protect trade in the North Atlantic.

ABILITY TO SEND A FLEET TO THE FAR EAST 19. The situation has been fully reviewed in Annex IV, from which it will be seen that we intend to send a battle cruiser and carrier to the Indian Ocean at the start of war with Japan.

Certain other heavy ships might be available, but their despatch to the Far East can only be considered in the light of the situation at the time. Our ability to send capital ships to the Far East depends on:-

(a) The strength and location of the German Fleet.

(b) The success that attends our land and sea operations in the Eastern Mediterranean theatre.

(c) Our own capital ship strength.

(d) The likelihood of invasion of the United Kingdom.

None of these is a factor which can be forecast with accuracy in advance.

It would be misleading to attempt to lay down possible strengths for the Far East and proposed movement time-tables. It is vital to avoid being weak everywhere. All we can say is that we should send a battle cruiser and a carrier to the Indian Ocean. Our ability to do more must be judged entirely on the situation at the time.


20. Mr. Menzies has also raised the question of the protection of troop convoys in the Indian Ocean in the event of war with Japan.


21. The Singapore Conference considered capital ship escort would be necessary for troop convoys in the Indian Ocean. The A.D.A.

Conference in February 1941 [4] recommended that the policy should be to provide capital ship cover. The New Zealand Chiefs of Staff and the Australian Government insist that escort, not cover, should be provided. [5]

22. Initially we shall only have one capital ship in the Indian Ocean. To provide capital ship escort for troop convoys it will, at first, be necessary to accept reduced frequency in sailings.



23. Mr. Menzies has emphasised the importance which the Commonwealth Government attaches to the provision of the aircraft necessary for local security and trade protection, particularly in view of the situation governing the disposition of capital ships.

He has stated that the present strength of the Australian Air Force is inadequate for these purposes.

24. The Air Ministry has already discussed this question with the Prime Minister of Australia and has furnished him with an Air Staff examination of the Australian paper 'Proposed Organisation of the Royal Australian Air Force' and a paper relating to Australian aircraft production by the Minister of Aircraft Production. [6] The position regarding aircraft supplies from the United Kingdom production is attached.

25. Mr. Menzies has had a further meeting with the Secretary of State for Air [7] and the Minister of Aircraft Production on the 10th April, when these questions were discussed.

26. Mr. Shedden [8] has subsequently requested a statement of the expansion plans of the Royal Air Force, to give the Prime Minister a complete frame for the picture of Australia's air effort. In compliance with this request, a copy of Target Programme 'C', which still forms the basis of the air expansion programme, has been handed to Mr. Menzies. This copy includes the present Royal Air Force Order of Battle and, owing to its particularly secret nature, it is not reproduced as an annex. This expansion programme is subject to modification; and increase in heavy bombers at home has already been commenced at the expense of medium bombers, and the possibility of increasing the heavy bomber force to the maximum practicable extent is under urgent examination.



27. Mr. Menzies has asked, in paragraph 9 of his Memorandum, for the views of His Majesty's Government on the possibility of obtaining United States of America co-operation in support of a declaration which might deter Japan from action and on the possibility of agreement on drawing a line to indicate the point of aggression by Japan.

Mr. Menzies also draws attention to the Australian Government's concern regarding the grave potential threat against the security of Singapore and Australia, by shore-based aircraft, should Japan attempt to establish herself in the Netherlands East Indies.


28. This point will be dealt with separately as a matter of Government policy.

ACT OF WAR BY JAPAN 29. Paragraph to of Australia Telegram No. 187 dated the 27th March 1941 [9], expresses agreement with the views held by the Chiefs of Staff that a decision as to what constitutes an act of war by Japan should only be made by all the Governments concerned in the light of the circumstances at the time. We are fully alive to the serious military disadvantages which consultation between all the Governments concerned will occasion, but we feel that, in view of the very grave implications which hostilities with Japan would bring about, this consultation is essential.

30. It is understood that Mr. Menzies is anxious to convey to His Majesty's Government in the Commonwealth of Australia the present views of His Majesty's Government in the United Kingdom as to their probable attitude in the event of Japanese aggression in Thailand, the Netherlands East Indies, Portuguese Timor, New Caledonia and the Loyalty Islands.

31. If we had a definite assurance of American intervention in the event of Japanese aggression in any of these areas, there is no doubt that it would be to our advantage that His Majesty's Government should immediately declare war on Japan.

If, on the other hand, it appeared likely that the United States of America would fail to intervene, we could not recommend the adoption of a definite policy under which Japanese aggression against these areas should under all circumstances be treated automatically as a casus belli. Each case would have to be judged on its merits in the light of the then existing situation.



32. Mr.Menzies has referred in paragraph 9 of his Memorandum to the specific point that any attempt by Japan to establish herself in the Netherlands East Indies would be viewed in Australia as a grave threat against the security of Singapore and Australia, which should be resisted. He points out that, if Japan should establish herself in the Netherlands East Indies, a scale of air attack which is now limited to seaborne aircraft would become transformed into a much graver one by land-based aircraft.


33. We agree that, if the Japanese succeeded in establishing themselves in the Netherlands East Indies, they would be a serious threat to both Australia and Singapore, as Japan would gain control of all sea routes through the Netherlands East Indies, the air route to Australia would be cut, and a considerable scale of air attack could probably be developed against Singapore. The threat of direct air attack on Australia would, however, not be a serious one.

The scale of attack is briefly reviewed below.

34. On the assumption that other commitments remain as at present, the total number of aircraft that the Japanese could make available for operations based on the Netherlands East Indies would be about 450 (150 fighters, 150 light bombers and 150 heavy bombers). This would leave no aircraft for attacks on British territory from Thailand.

35. The existence of only one aerodrome with facilities for the operation of heavy bombers within range of Australia (Kendari, Celebes) would limit the scale of attack on Australia to a maximum of 40 to 50 aircraft, operating at extreme range over the Timor Sea-a scale of attack which would probably in practice be negligible and would be limited to the immediate vicinity of Darwin.

36. As regards Malaya, however, heavy -bombers could be based on aerodromes in Western Java, where there is accommodation for 100 to 150, and, if the formidable supply difficulties could be overcome, light bombers and fighters could be based on Sumatra, where there is accommodation for some 150 to 200. A total of some 320 aircraft (50 fighters, 150 light bombers and 120 heavy bombers) could thus be operated against Malaya. [10]

[matter omitted]


C. F. A. PORTAL [12]

R. H. HAINING [13]


1 Paper no. 7A, 'Strategical Questions and Objectives in Strength', dated 29 March. This memorandum, and several other papers mentioned below, were originally attached to this document as annexes. They are not reproduced here but are available on file Defence: Special Collection 1, Box 633, Prime Minister's Visit Abroad, 1941. Review of Defence Position in the Pacific. War Cabinet Agendum No. 195/1941.

2 Document 236.

3 This is probably a reference to the discussions between Menzies and the Admiralty held on 28 March. See Document 343, note 5.

4 For a copy of the report of the Anglo-Dutch-Australian Conference see AA: A2671, 109/1941, particularly Annexe C.

5 See Document 366, and N.Z. Govt's cablegram 109 of 23 March to the U.K. Dominions Secretary, repeated to the Commonwealth Govt as no. 52 (on file AA: CP290/6, 70).

6 Lord Beaverbrook.

7 Sir Archibald Sinclair.

8 Secretary of the Defence Co-ordination Dept, who was then in London with Menzies.

9 Document 366.

10 Menzies informed the Acting Prime Minister, A. W. Fadden, of the main points in this document in cablegram M88 of 27 April. See file AA: A1608, V41/1/1.

11 Chief of the U.K. Naval Staff.

12 Chief of the U.K. Air Staff.

13 Vice Chief of the Imperial General Staff.